Question

Write all the factors of the given numbers and list their common factors.
(1) 12, 16 (2) 21, 24 (3) 25, 30 (4) 24, 25 (5) 56, 72

Answer 1

(1)
Factors of 12: 1, 2, 3, 4, 6, 12

Factors of 16: 1, 2, 4, 8, 16

Common factors of 12 and 16: 1, 2, 4

(2)
Factors of 21: 1, 3, 7, 21

Factors of 24: 1, 2, 3, 4, 6, 8, 12, 24

Common factors of 21 and 24: 1, 3

(3)
Factors of 25: 1, 5, 25

Factors of 30: 1, 2, 3, 5, 6, 10, 15, 30

Common factors of 25 and 30: 1, 5

(4)
Factors of 24: 1, 2, 3, 4, 6, 8, 12, 24

Factors of 25: 1, 5, 25

Common factors of 24 and 25: 1

(5)
Factors of 56: 1, 2, 4, 7, 8, 14, 28, 56

Factors of 72: 1, 2, 3, 4, 6, 8, 9, 12, 18, 24, 36, 72

Common factors of 56 and 72: 1, 2, 4, 8